JP2001120932A - Filter unit and filter device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the performance of filtering oil mist contained in fluid and also to prolong the life of a filter unit and to miniaturize a filter device. SOLUTION: The filter unit 1 is constituted so that a space part 9 for storing oil 25 flowing from a primary filter 2 is formed between a cylindrical primary filter 2 and a cylindrical secondary filter 3 and an oil outlet 10 is formed at the bottom part of the space part 9. In such a way, main part of the oil 25 in the oil mist is captured by the primary filter 2, and a minute amount of the oil 25 as the fine particles passing through the primary filter 2 is captured by the secondary filter 3. The mach part of the oil 25 captured at the primary filter 2 is stored in the space part 9 and made to flow from the oil outlet 10 and recovered. In such a way, the life of the filter unit 1 is prolonged, moreover the filter unit 1 is made small and the filter device 11 is miniaturized by fitting the primary filter 2 and the secondary filter 3 in the relation of the outside and the inside.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a filter unit and a filter device for separating and recovering oil in an oil mist.

[0002]

2. Description of the Related Art For example, in the case of machining, oil mist is generated as oil mist due to scattering of oil during processing or heat, which deteriorates the environment of a work site. In the above example, it is strongly required to remove such oil mist and purify the air.

[0003] Exhaust gas regulations for automobiles are becoming stricter year by year. In particular, it is expected that a diesel engine vehicle will be required to equip a blow-by gas closed system. Therefore, in a diesel engine, it is urgently necessary to purify blow-by gas (oil mist) contained in a crankcase.

[0004] In order to purify the oil mist as described above, it is preferable to capture and separate the oil in the oil mist with a primary filter having a coarse mesh, and further capture the oil that has passed through the primary filter with a secondary filter. It is believed that. Further, it is also required to extend the life of the primary and secondary filters by collecting the separated oil.

On the other hand, as a filter device having a primary filter and a secondary filter, there is a filter device in which a primary filter and a secondary filter are mounted in one housing.

[0006]

As described above, the filter device in which the primary filter and the secondary filter are mounted in one housing captures most of the oil in the oil mist with the primary filter having a coarse mesh. Fine oil of the particles separated and passed through the primary filter is further captured by a secondary filter. In such a filter device, since the primary filter and the secondary filter are separately arranged in different shapes, it is necessary to increase the filter accommodation space in the housing, and there is a problem that the filter device becomes large.
Also, there is no effective structure for recovering the oil captured by the primary filter.

As a general filter device, there is also a filter device in which a primary filter and a secondary filter are formed in a cylindrical shape, and a filter unit in which both are fitted in a contact state with each other is mounted on a cylindrical housing. Although such a filter device can be downsized, it does not separate and collect the oil in the oil mist.

An object of the present invention is to effectively separate and recover oil in an oil mist, and to further extend the life of a filter unit.

An object of the present invention is to contribute to a reduction in the size of a filter device.

[0010]

According to a first aspect of the present invention, there is provided a filter unit comprising: a cylindrical primary filter for capturing oil in an oil mist; and a cylindrical secondary filter for capturing oil passing through the primary filter. The primary filter and the secondary filter are loosely fitted so that an annular space for storing the oil flowing from the primary filter is formed between the two, and the bottom of the space is provided therein. An oil outlet for discharging the accumulated oil is formed.

Therefore, when the primary filter and the secondary filter are placed in the flow of the oil mist, most of the oil in the oil mist is trapped by the primary filter, and fine and minute particles of the particles passing through the primary filter are removed. Oil is trapped in the secondary filter. Most of the oil trapped in the primary filter flows by collecting particles, but this oil is stored in the space and flows from the oil outlet.

According to a second aspect of the present invention, in the first aspect of the present invention, a perforated pipe having a through hole in a peripheral surface is fitted to a boundary surface between the space and the primary filter.

Therefore, the oil flowing from the primary filter can be guided toward the bottom of the space by the perforated pipe. Further, when the flow rate of the fluid is high, fine oil of particles heading to the secondary filter is received by the perforated pipe, so that the oil can easily stay in the space.

According to a third aspect of the present invention, the filter unit according to the first or second aspect is mounted on a housing having an inlet and an exhaust port for taking in the oil mist, and the oil flow of the filter unit is mounted on the housing. An oil recovery port communicating with the outlet is formed.

Therefore, when the oil mist is fed from the inlet of the housing, most of the oil in the oil mist is captured by the primary filter, and the small amount of fine oil passing through the primary filter is captured by the secondary filter. The purified gas is discharged from the exhaust port. Most of the oil trapped in the primary filter collects and flows particles,
This oil is stored in the space and flows from the oil outlet. Oil accumulated in the housing can be recovered from the oil recovery port.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. 1 is a vertical sectional side view of the filter unit, FIG. 2 is a horizontal sectional view taken along line AA in FIG. 1, and FIG.
Is a longitudinal side view of the filter device, and FIG. 4 is a graph showing experimental results of filtration performance.

In the figure, reference numeral 1 denotes a filter unit. The filter unit 1 includes a cylindrical primary filter 2, a cylindrical secondary filter 3 having a smaller mesh and a smaller outer diameter than the primary filter 2, and a plurality of through-holes 4 formed in the peripheral surface. It comprises an opening pipe 5, an inner pipe 6, and two end plates 7, 8 made of synthetic resin. The ends of the primary filter 2, the secondary filter 3, the perforated pipe 5, and the inner pipe 6 are positioned and fixed to the end plates 7, 8, respectively.

That is, the primary filter 2 is located on the outermost side, and a perforated pipe 5 is fitted to the inner surface of the primary filter 2 in a close state, and the secondary filter 3 has a space 9 between itself and the inner peripheral surface of the primary filter 2. The inner pipe 6 is loosely fitted inside the primary filter 2 so as to be formed, and the inner pipe 6 is fitted close to the inner peripheral surface of the secondary filter 3. A number of oil outlets 10 communicating with the space 9 are formed in one end plate 8 which is lower in use.

In the present embodiment, the end plates 7 and 8 are formed by setting the primary filter 2, the secondary filter 3, the perforated pipe 5 and the inner pipe 6 in a molding die for molding them, and forming a cavity in the molding die. It is molded by injecting the material into By this molding process, the primary filter 2, the secondary filter 3, the perforated pipe 5, the inner pipe 6, and the end plates 7, 8 are integrally connected as a unit. Note that the end plates 7 and 8 may be formed of a metal such as an iron plate.

Next, the configuration of the filter device 11 in which the filter unit 1 is mounted will be described with reference to FIG. Housing 12 on which filter unit 1 is mounted
Comprises a housing body 13, a hemispherical cap 14, and a connection port 15. Housing body 13 and cap 1
4 are screwed to each other, and the screwed portion of both is
6 sealed. The connection port 15 is fixedly fitted to the housing body 13. Housing body 1
3, an inlet 17 for taking in oil mist is formed,
The connection port body 15 has an exhaust port 18 connected to the inside of the housing body 13. A connection port 20 having an oil recovery port 19 communicating with the oil outlet 10 of the filter unit 1 is screwed into the center of the bottom of the cap 14.

The filter unit 1 is fixed with the lower end plate 8 pressed by a spring 21 and the upper end plate 7 in contact with the step 22 of the housing body 13. In this state, the space between the outside of the filter unit 1 and the cap 14 is sealed by the seal member 23, and the space between the inside of the filter unit 1 and the housing body 13 is sealed by the seal member 24.

In such a configuration, when the oil mist is fed from the inlet 17, the oil mist passes through the primary filter 2, the through hole 4 of the perforated pipe 5, and the secondary filter 3 as shown by arrows, and Is the inner pipe 6
Is discharged from the exhaust port 18 through the through hole 4. In this process, most of the oil 25 in the oil mist is removed from the primary filter 2.
And a small amount of fine oil 25 of the particles passing through the primary filter 2 is captured by the secondary filter 3.

Here, most of the oil 25 captured by the primary filter 2 collects and flows out, but the oil 25 is stored in the space 9 without adhering to the secondary filter 3. The oil 25 stored in the space 9 flows along the end plate 8 and drops from the oil outlet 10, so that the oil 25 can be collected from the oil recovery port 19. In the present embodiment, since the perforated pipe 5 is provided inside the primary filter 2, the oil 2 flowing from the primary filter 2
5 can be quickly guided toward the bottom of the space 9 by the perforated pipe 5. Furthermore, when the flow rate of the oil mist is high, the fine oil 25 of the particles heading to the secondary filter 3 is received by the perforated pipe 5 and can be easily stagnated in the space 9. That is, the oil 25 having a fine particle passing through the primary filter 2 can be stored in the space 9. Thereby, the recovery efficiency of the oil 25 can be further increased.

Further, the oil 25 captured by the primary filter 2
Can be recovered, so that the life of the filter unit 1 can be extended.

Here, FIG. 4 shows experimental results of the filtering performance of the filter device 11 of the present embodiment and the filter device as a comparative example. A filter device as a comparative example is a filter unit configured by contacting a cylindrical primary filter and a secondary filter with each other,
This is a filter device mounted on one housing, and the filter unit includes the filter unit 1 of the present invention.
There is no space portion 9 for storing oil as shown in FIG.

The vertical axis in FIG. 4 is the inlet pressure, and the horizontal axis is the amount of oil administered to the filter unit. As the amount of oil increases, the fluid becomes less likely to pass through the primary and secondary filters, so that the pressure at the inlet (corresponding to the inlet 17 of the housing 12) increases. The dotted line shows the filtration performance of the filter device as a comparative example.
As soon as approximately 100 g of oil was dosed into the filter unit, the inlet pressure reached 300 mmAq. This means that the oil trapped by the primary filter adhered to the secondary filter and the fluid became difficult to pass. The solid line shows the filtration performance of the filter device 11 of the present invention. When approximately 100 g of oil is injected into the filter unit 1, the inlet pressure becomes approximately 190 mm.
Low with Aq. This is because when the filter unit 1 of the present invention is used, oil flows into the space 9 and is difficult to adhere to the secondary filter 3. The inlet pressure reached about 300 mmAq when about 150 g of oil was dosed. This is because fine oil of particles that cannot be captured by the primary filter 2
It is considered that the amount of the captured oil exceeded a certain value, and it was difficult for the fluid to pass through the secondary filter 3.

According to the results of FIG. 4, the filter device 11 using the filter unit 1 in which the space 9 is formed between the primary filter 2 and the secondary filter 3 as in the present invention.
It can be seen that the filtration performance is superior to the filter device of the comparative example.

As described above, since the primary filter 2 and the secondary filter 3 are formed in a cylindrical shape and fitted on substantially concentric circles, the size of the filter unit 1 can be reduced, and the filter device can be reduced. 11 can be reduced.

[0029] Such a filter device 11 receives blow-by gas from the crankcase of a diesel engine at the inlet 1.
7, purified by the filter unit 1, and the purified fluid is discharged to the atmosphere, or can be used when returning to the intake system through an air cleaner.
Furthermore, air with a bad working environment is taken in from the inlet 17,
It can be used when purifying by the filter unit 1.

In the above embodiment, the primary filter 2 is arranged on the outside and the secondary filter 3 is arranged on the inside. However, the primary filter having a coarse mesh is arranged inside, and the secondary filter having a dense mesh is arranged outside. To form a filter unit. When such a filter unit is used, oil mist may be taken in from the inside of the primary filter of the filter unit, and the fluid that has passed through the primary filter may be discharged from the outside of the secondary filter. At this time, the flow of the fluid is in a direction opposite to the direction of the arrow in FIG.

[0031]

According to the filter unit of the present invention, an annular space for storing oil flowing from the primary filter is formed between the cylindrical primary filter and the cylindrical secondary filter, and the bottom of the space is formed. Has an oil outlet, so
When the primary filter and the secondary filter are placed in the flow of the oil mist, most of the oil in the oil mist is captured by the primary filter, and fine oil of particles that have passed through the primary filter is captured by the secondary filter. Can be. Most of the oil captured by the primary filter is stored in the space, and can be recovered by flowing out from the oil outlet. Thereby, the life of the filter unit can be extended. Furthermore, since the primary filter and the secondary filter are formed in a cylindrical shape and are fitted in a relationship between the outside and the inside, the size of the filter unit can be reduced, which contributes to downsizing of the filter device. be able to.

According to the second aspect of the present invention, in the first aspect of the present invention, a perforated pipe having a through hole in a peripheral surface is fitted to a boundary surface between the space and the primary filter. The oil flowing from the filter can be guided toward the bottom of the space by the perforated pipe. Furthermore, when the flow velocity of the fluid is high, fine oil mist of particles heading for the secondary filter is received by the perforated pipe, so that the oil mist can be easily stagnated in the space. Thereby, the oil collection efficiency can be further increased.

According to the third aspect of the present invention, there is provided a filter device.
Or the filter unit described in 2 is mounted on a housing, and an oil recovery port communicating with an oil outlet of the filter unit is formed in the housing, so that when the oil mist is fed from the inlet of the housing, the oil mist is generated. Most of the oil can be captured by the primary filter, the small amount of fine oil passing through the primary filter can be captured by the secondary filter, and the purified gas can be discharged from the exhaust port. Most of the oil trapped by the primary filter is stored in the space, can flow out from the oil outlet, and can be recovered from the oil recovery port. Thereby, the life of the filter unit can be extended. Furthermore, since the primary filter and the secondary filter are formed in a cylindrical shape and fitted in a relationship between the outside and the inside, the size of the filter unit and the filter device can be reduced.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view of a filter unit according to an embodiment of the present invention.

FIG. 2 is a horizontal sectional view taken along line AA in FIG.

FIG. 3 is a vertical sectional side view of the filter device according to one embodiment of the present invention.

FIG. 4 is a graph showing experimental results of filtration performance.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Filter unit 2 Primary filter 3 Secondary filter 4 Through-hole 5 Perforated pipe 9 Space part 10 Oil outlet 12 Housing 17 Inlet 18 Exhaust port 19 Oil recovery port 25 Oil

Continued on the front page F term (reference) 4D058 JA02 JB24 JB29 KA01 KA03 KA14 KA23 KA25 KB12 KC04 KC30 KC32 KC55 KC62 KC90 LA05 QA01 QA06 RA11 SA06 SA15

Claims (3)

[Claims] 1. A cylindrical primary filter for capturing oil in an oil mist, and a cylindrical secondary filter for capturing oil passing through the primary filter, wherein the primary filter and the secondary filter are An oil outlet is formed between the two so that an annular space for storing oil flowing from the primary filter is formed, and an oil outlet for discharging the oil stored in the space is formed at the bottom of the space. A filter unit. 2. The filter unit according to claim 1, wherein a perforated pipe having a through hole on a peripheral surface is fitted to a boundary surface between the space and the primary filter. 3. The filter unit according to claim 1, wherein the housing has an inlet for taking in the oil mist and an exhaust port, and the housing has an oil recovery port communicating with the oil outlet of the filter unit. Is formed.